An Illinois man is behind bars for murder, but his identical twin brother says he really committed the crime. Despite the alleged confession, a judge ruled Tuesday that there would be no retrial in the case, calling the admission "completely uncredible" and noting a previous pattern the men had of switching places with one another.

Kevin Dugar, pictured on the left, was convicted in 2005 of killing a rival gang member and wounding another in Chicago, according to the Chicago Tribune. He has been serving his 54-year sentence ever since, but in 2016 his identical twin brother Karl Smith, who is also behind bars, testified that he had really committed the crime.

Dugar's attorney, Karen Daniel, was hoping the admission would earn her client a new trial.

"If we had a retrial, we'd have a huge piece of evidence in favor of Karl having committed the crime: a confession that frankly could be used to convict him if the state was so inclined," Daniel said in court Tuesday, according to the local newspaper.

But Cook County Judge Vincent Gaughan questioned Smith's motivation behind the confession, noting that Smith's own 99-year-sentence for a 2008 home invasion and armed robbery that ended with a 6-year-old boy getting shot in the head, could have factored into his decision to admit to his brother's alleged crime.

Smith allegedly came forward with his confession after an appeal in his own case had been denied.

"Did he have anything to lose? No," the judge said, according to the Tribune. "I find (Smith's) testimony completely uncredible. No weight whatsoever should be given to his testimony."

He also referenced a habit the two had of pretending to be one another, which he said further demonstrates "a pattern of misdirection and deceit."

During Dugar's trial, Ronnie Bolden, who was injured during the 2003 shooting, referred to the gunman as "Twin"; however, the moniker had been used by both men on the street, WMAQ-TV reports.

Bolden reportedly waited more than a month to identify the shooter because he had planned to take care of the matter "on the street," a petition requesting Dugar's new trial said. At the time of the incident, prosecutors said Bolden's gang, known as the Black P Stones, had been fighting with the Conservative Vice Lords, a gang that both twins were reportedly members of, according to the Tribune.

After Gaughan denied the request this week to re-try to case, Dugar wiped away a tear. He's expected to be released from prison in 2056, when he'd be in his late 70s.

[Photos: Illinois Department of Corrections]

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